Highly radiation-sensitive telomerized polyesters



United States Patent 3,485,732 HIGHLY RADIATION SENSITIVE TELOMERIZEDPOLYESTERS Gaetano F. DAlelio, South Bend, Ind., assignor, by

mesne assignments, to PPG Industries, Inc., Pittsburgh, Pa., acorporation of Pennsylvania No Drawing. Filed Mar. 2, 1966, Ser. No.531,056 Int. Cl. B01 1/10; 'C08d 1/00; C08f 1/16 US. Cl. 204-15915 20Claims ABSTRACT OF THE DISCLOSURE Telomerized diacrylyl polyesters areobtained from the condensation of a glycidyl ester with a saturatedaliphatic polycarboxylic acid or a linear polyester of such an acid.These polyesters have the formula:

CHE-(I3COOCHZCHCH2OOORCO[OROOCRCOL;

where n is 0 to 14, R is a single valence bond or a divalent saturatedaliphatic hydrocarbon radical; R is a divalent saturated aliphatichydrocarbon radical. R" is hydrogen or methyl, R" is hydrogen or analiphatic hydrocarbon radical, and x is hydrogen or an acyl radical ofthe formula R"CO. These polyesters cure when subjected to relatively lowdoses of ionizing radiation.

This invention in general deals with radiation-sensitive polymers.Particularly it concerns viscous, soluble, flowable, relatively lowmolecular weight polymers, known as oligomers, which, when subjected toionizing radiation become insoluble and infusible. More specifically, itdeals with telomerized polyesters which, on irradiation, convert tothree-dimensional crosslinked, insoluble, infusible polymers atrelatively low doses of ionizing radiation.

The telomerized polyesters used in the practice of this invention arelinear polyesters which are derived from the condensation of a glycidylacrylate with a saturated aliphatic, including cycloaliphatic,polycarboxylic acid or with a linear condensation polymer of suchpolycarboxylic acids and saturated aliphatic, including cycloaliphaticpolyhydric alcohols. These telomerized polyesters have as end groups thehighly radiation-sensitive group.

These telomerized polyesters can be represented by the general formula IO CHzIFHCHzO O C C=CH2 wherein n has a value of O to 14; R represents aconnecting linkage between two adjacent carboxyl radicals selected fromthe class consisting of a single valence bond and a divalent saturatedaliphatic hydrocarbon radical having 110 carbon atoms; R represents adivalent saturated aliphatic hydrocarbon radical (includingcycloaliphatic) having 1l0 carbon atoms; R" represents hydrogen or CH R"represents hydrogen or an aliphatic hydrocarbon radical (saturated orunsaturated) having 1-18 carbon atoms; and X represents hydrogen or anacyl group having the formula R""CO. The radical-OOCRCOOcan be definedas the dicarboxylic 3,485,732 Patented Dec. 23, 1969 radical derivedfrom a saturated aliphatic dicarboxylic acid such as oxalic, malonic,succinic, glutaric, adipic acids, etc.

These highly radiation-sensitive telomerized polyesters are preparedfrom appropriate acrylyl derivatives such as the glycidyl esters,

RI! CHg=-COOCH2CH CH2 R(COOH)Q+ZCHZ-(IICOOCHQCE on2 a O R" cHFI: c oOHzCHCHzO o 0-a-c o 0 011201101120 0 c d=crn on 11 (Eg.1a)

Similarly a dicarboxyl terminated aliphatic polyester can be reactedwith glycidyl acrylate to produce linear hydroxyl substitutedradiation-sensitive polyesters, thus (1% 1)R(OOOH) nR(OH)HOOCRCOIOROOCRCOLOH then HOOCRGO[OROOCRCO]HOH This second class ofoligomers can be represented by the formula of equation 1b whichincludes that of Equation In when n=0, and of the higher molecularweight oligomers when n equals 1-14.

The hydroxy substituted oligomeric acrylyl terminated polymer esters asrepresented broadly by equations la and 1b have specific and improvedutility especially when polymerized in the presence of cellulose such aswood, paper, fibers, fiber board, etc., in the form of a coating,impregnant or bonding agent. The presence of the alcoholic hydroxylcauses improved wetting of cellulose and because of hydrogen bonding ofthe hydroxyl group with the cellulose, yields improved adhesion comparedto the unsubstituted oligomeric polyesters of Equation 1a to lg.

In those cases where the presence of these hydroxyl groups is notdesired or is detrimental to such properties as dielectric constant orpower factor, the hydroxyl groups can be converted to ester groups byacylation with aliphatic acids, R""COOH wherein R"" is H or an aliphaticsaturated or unsaturated hydrocarbon group containing 1 to 18 carbonatoms, such as formic, acetic, propionic, butyric, acrylic, methacrylic,oleic, stearic acid, etc., or their anhydrides forming a class ofoligomeric polyesters suitable in the practice of this invention, thus:

RI! RI! l CH2=CCOOOHZCHCHZOOCRCOOCHZCHCHQOOCC=CH2 2R COOH lCII2=CCOOCHzCHCIIzOOCR-COOCHzCHCHzOOCR=CH2 (Eq.2a)

OCR/I II OCR/I II RI! RI! l Hz=cC00CHzCHOH2O0GRCO[OR'O0on0o],.0CH oH0H00Cd:CIIg 2R "C0011 OH OH RI! RI! IOIL-=0COOCH2CHCHzOOCR-CO[OROOCROOhOCHzCHCH OOOJ=CH2 (Eq.2b)

OCRIIII OOCRI! I! The radiation-sensitive oligomeric polymers ofEquations hydroxyalkyl esters may be used in the synthesis of these 2aand 2b are particularly useful especially when admixed polyesters, andalso instead of the diols, R(OH) the with other unsaturated polymericalkyd esters such as corresponding alkylene oxides, polyethylenemaleate, polyethylene fumarate, etc. The

formula of Equation 2b represents the third class of radiation-sensitivetelomerized polyesters wherein n has a value of 0 to 14. O

Acrylation of the hydroxy substituted telomerized polyesters of Equation1b by means of an acrylic acid, or its can, when available, also beused, wherein R is H or an acrylyl anhydride or chloride produces aclass of teloalkyl group containing 1 to 10 carbon atoms. merizedradiation-sensitive polymers which, because of the Telomerizedpolyesters with a greater number of repeatincreased number of acrylylgroups, shows an even more ing segments, and therefore of highermolecular weight improved response to ionizing radiation, thus than thesimplest polyesters, are prepared by increasing RI! R R OHJC00CH2CH0H200CR0 0[0 ROOCRC 01,0 CH CHOH2OOCC=CH2 (CH2=( JCO)2O OH HRI! RI! C1-I2= C O 0 CHZCHCHQO 0 CRC 0[0 RO 0 0 RC 0],.0 CHzCHCHzO 0 C CJ=CHQ (Eq. 3)

RI! RI! I l OH2=CCO OCC=CH2 Simple telomerized polyesters of thisinvention can be the ratio of the n moles of diol and the n+1 moles ofdi- P 'FP Q flfom the F P of two moles of a Saturated carboxylic acid tothe 2 moles of glycidyl acrylate to mainahPhatlc dlcarboxyhc acldR(COOH)2 one mole of a tain the molar ratio of diol:diacid:glycidylacrylate at diol, R'(OH) and two moles of a glycidyl ac y +1) :2. Thusit may be seen that a simple Polyester is obtained with one mole ofdiol; two moles of diacid OHFC-COOCH2CHCH2 and two moles of glycidylacrylate. When the value of n to give aproduct of the general formula isincreased for the diol to 2, the value for the diacid B OX 0X R forexample becomes 3 and that for the acrylic function remains con-CHFCHCOOCHzCHOHzOOCCHzOHzCOO Stant at OX CH The linear polyesters can beprepared by various types of standard reactions used in preparing estersstarting with CH2 acids or their anhydrides or acid halides and glycolsor CHFCHCO O CHZ?HCH2O 0 0 052011200 0 alkylene oxides. The conditionsused are those appropriate OK for the normal reaction of alcohols withacids, anhydrides Instead of the free acids, R(COOH) suitable derivaandacid halides to form esters, and also those normally tives such as theiranhydrides, acid chlorides, or omega used for the reaction of theglycidyl group with acids.

CH2=C o 0 0 01120110112 I I! RI! RI! I I CHFCCQQ 01110110520 0 CBC 0OR() 0on0 0 oonitllncmoo OC==CH2 OH H 6 This product can be converted tocompounds in which X to about 8800 for 11 equal to 14 when the diacid isdecencrepresents an acyl radical by reaction with an appropriatedicarboxylic acid and the diol is dodecanediol. acyl halide such asacrylyl chloride, or acyl anhydride Some illustrative examples of thevarious HOROH such as acetic anhydride, to give the desired acylderivaalcohols which can be used in synthesizing the telornerized tive.5 polyesters used in this invention are ethylene glycol, tri-CIIFCCO0CH2CHCH2 .1 it 0 CHFCC0OCHZCHCHZOOCRCOOR'OOCRCOOCH:CHCH2OOCC=CH2 I 011 H R CHZZC C O OCHgCHCHz In the above formulas the derivative portion of the methyleneglycol, tetramethylene glycol, 2,3-dihydroxyglycidyl acrylate componentare represented by the strucbutane, 1,4-dihydroxybutane,1,4-dihydroxy-2-ethylbuture tane, 1,6-dihydroxyhexane,1,8-dihydroxyoctane 2,10-di- C HFC C O O CHECHCH? hydroxydecane,1,4-dihydroxycyclohexane, 1,4-dimethyll Cl)i olcyclohexane,2,2-diethyl-propanediol-l,3, 2,2-dimethylpropanediol-l,3,3-rnethylpentanediol-1,4 2,2-diethylbutanediol-1,3,4,5-dihydroxynonane,pentamethylene glycol, heptamethylene glycol, nonamethylene glycol,decamethylene glycol, diethylene glycol, triethylene glycol, propyleneglycol, dipropylene glycol, 2-ethylhexanediol-l,3, etc.

However, it is recognized that the oxirane ring of the glycidyl groupmay react so that the isomeric structure CH:0X Alkylene oxides can alsobe used to give corresponding may be formed. It is intended that both ofthese isomeric glycol dfifivativfisl Such as P py Oxide, ethylene OXlde,structures are covered by the various formulas given here- Y f i b Somelllustranve examples of the various Ohgomers 1n which the value of n islarger than 1 are HO O C R c OOH readily prepared by the same reactionsas given hereinabove by simply changing the ratio of the diol to theacids which can be used in preparing the telornerized desired value of nand that of the diacid to n+1 While polyesters used in the practice ofthis invention are oxalic, maintaining the molar quantity of the acrylicmoiety at malonic, succinic, adipic, glutaric, sebacic, methyl suc- 2,thus cinic, pimelic, 2,3-dimethyl-succinic, suberic, hexyl-sucl l i!CH2=CCOOCHZ$HCH2OOCROO[OR OOCRCO11 OCH2$HCH2OOCCiCHZ OH OH /2R" COCl i!i cn2=ocoocrnorrcrnoooucmoa'oooaoo noornorrorrzooo 0:0 1,

Depending on the nature of R, R and R" the viscosity cinic,1,3-hexahydrophthalic, 1,3-hexahydrophthalic, 1,4- of these telornerizedpolyesters increases from about 100 hexahydrophthalic,1,1-cyclobutanedicarboxylic acid, to 9000 centistokes at 20 C. as thevalue of n increases trans-1,4-cyclohanedicarboxylic,3,3-diethyl-glutaric acid, from 1 to 14. Also depending on the values ofn, R and 3,3-dimethyl-glutaric, 2,2-dimethyl-glutaric, 2,2-dimethyl- R",the molecular weight of these telomerized esters will succinic,2-keto-glutaric, diglycollic acids, etc. vary from about 275 for thelowest one at a value of 22:1 It is most important to note that thevarious classes of crosslinks at about 2 megarads, whereas thecorresponding phthalyl derivative,

CHFC o o[o CH2CH2O o CGH4C 0]..0 CHgCHgO o o C=CH and the correspondingxylyl derivative both require 12 and 14 megarads respectively, to becomeinsoluble and infusible.

This difference is surprising particularly because these threetelomerized esters all cure with radical initiators such as with 1%benzyl peroxide in about 90 to 95 seconds at 100 C., and with redoxsystems of cobalt and tertiary butyl hydroperoxide in three to three andonehalf hours at room temperature. This difference is due, apparently,to the fact that aromatic ring compounds such as phenyl, naphthyl andthe like are energy sinks for irradiation.

It will be noted too that the aliphatic hydrocarbon structures in thepolycarboxylic and polyhydric alcohol segments are saturated. This isfor the purpose of avoiding brittleness and reducing susceptibility tooxidation and discoloration in the irradiated products. By havingunsaturation in the acrylyl groups at the ends of the telomerizeddiacryl polyester, the product is more ductile.

The term irradiation, as used herein, means high energy radiation and/orthe secondary energies resulting from conversion of this electron orother particle energy to neutron or gamma radiation, said energies beingat least equivalent to about 100,000 electron volts. While various typesof irradiation are suitable for this purpose, such as X-ray and gammaand beta rays,.the radiation produced by accelerated high energyelectrons has been found to be very conveniently and economicallyapplicable and to give very satisfactory results. However, regardless ofthe type of irradiation and the type of equipment used for itsgeneration or application, the use thereof in the practice of theinvention as described herein is contemplated as falling 'within thescope of this invention so long as the ionization radiation isequivalent to about 100,000 electron volts.

While there is no upper limit to the electron energy that can be soapplied advantageously, the effects desired in the practice of thisinvention can be accomplished without having to go above about20,000,000 electron volts. Generally, the higher the electron energyused, the greater is the depth of penetration into the massive structureof the materials to be treated, and the shorter is the time of exposurerequired to accomplish the desired result. For other types ofirradiation, such as gamma and X-rays, energy systems equivalent to theabove range of electron volts are desirable.

It is intended that the term irradiation include what has been referredto in the prior art as ionizing radiation which has been defined asradiation possessing an energy at least suflicient to produce ions or tobreak chemical bonds and thus includes also radiations such as ionizingparticle radiation as well as radiations of the type termed ionizingeleetromagnetic radiation.

The term ionizing particle radiation has been used to designate theemission of electrons or highly accelerated nuclear particles such asprotons, neutrons. alpha-particles, deuterons, beta-particles, or theiranalogs. directed in such a way that the particle is projected into themass to be irradiated. Charged particles can be accelerated by the aidof voltage gradients by such devices as accelerators with resonancechambers, Van der Graatf generators, betatrons, synchrotons, cyclotrons,etc. Neutron radiation can be produced by bombarding a selected lightmetal such as beryllium with positive particles or high energy. Particleradiations can also be obtained by the use of an atomic pile,radioactive isotopes or other natural or synthetic radioactivematerials.

Ionizing electromagnetic irradiation is produced when a metallic target,such as tungsten, is bombarded with electrons of suitable energy. Thisenergy is conferred to the electrons by potential accelerators of over0.1 million electron volts (mev). In addition to radiations of thistype, commonly called X-ray, an ionizing electromagnetic radiationsuitable for the practice of this invention can be obtained by means ofa nuclear reactor (pile or by the use of natural or syntheticradioactive material. for example, Cobalt 60.

Various types of high power electron linear accelerators arecommercially available, for example, the ARCO type travelling waveaccelerator, model Mark I, operating at 3 to 10 million electron volts,such as supplied by High Voltage Engineering Corporation, Burlington,Mass, or other types of accelerators as described in United StatesPatent No. 2,763,609 and in British Patent No. 762,953 are satisfactoryfor the practice of this invention.

In the following examples, the radiation doses are reported in megarads,which represent 1,000,000 rads. A rad is defined as the unit of absorbeddose and is equal to ergs per gram.

Many monomers as well as polymers have been subjected to ionizingradiation to convert them to improved or modified products. However,irradiation processes have been primarily of scientific interest, andvery little use of such irradiation on polymer processes has been madeindustrially. This is primarily due to economic factors because of thecost of the ionizing radiation delivered to the system to be treated.For example, the well-known low-cost polyester systems which consist ofa mixture of about equal parts by weight of styrene monomer and ofunsaturated alkyd resin prepared from maleic or fumaric anhydride,phthalic anhydride and ethylene glycol or diethylene glycol can be moreeconomically polymerized by free radical initiators than by ionizingradiation which requires about 25 to 40 megarads, depending on theformulation.

Such systems can be improved somewhat, however. by elimination ofphthalic anhydride in the formulation of the polyester and substitutingthe higher cost monomeric acrylic esters for the styrene. Even in suchsystems, the economic factors are unfavorable not only because of themuch higher cost of the mixture but because of the high volatility ofthe acrylic or methacrylic esters used. Even in such cases theirradiation dose required is of the order of 18 to 20 megarads and thesystems are highly inhibited by oxygen. The addition of substances suchas acetone or methyl ethyl ketone can reduce the required dose to 9 to12 megarads. Even then the products possess the undesirable odor ofunpolymerized acrylic monomer.

In contrast, by the use of the acrylyl telomerized polyesters used inthe practice of this invention and described hereinabove, crosslinked,insoluble, infusible polymers can be prepared readily by subjecting thepolyesters to ionizing radiation in doses of less than 8 megarads and insome cases to doses of 0.5 megarad or less, generally preferably atleast about 1 megarad. Irradiation dosages in this range are economical.

Furthermore, the acrylyl components in these telomerized polyesters arelocated at the ends of the polyester chains where they can moreeffectively crosslink. More important, the acrylyl components comprise aminor portion of the composition, and are particularly economical whenthe value of n in these telomerized polyesters is at least 2. inaddition, because the molecular weight of the telomerized polyester ismuch higher than a corresponding simple monomer such as methylmethacrylate or ethyl acrylate, it can function in a single moleculeboth as monomer and as polymer.

This property of crosslinking at economical radiation doses ismaintained when these telomerized polyesters are admixed withunsaturated alkyd resins alone or in the presence of other polymersprovided the unsaturated alkyd resin and the other polymers are of thenonaromatic type, that is, they are free of aromatic rings which act asenergy sinks and retard the crosslinking reaction. One of the advantagesof these diacrylyl polyesters is their compatibility with various typesof resins, particularly polyester or alkyd types.

A few illustrative examples of suitable polymers which may be dissolvedin or mixed with the telomerized polyesters of this invention, alongwith the unsaturated alkyd resins, are the non-aromatic type polymerssuch as polyvinyl acetate, polyethyl acrylate, polymethyl methacrylate,cellulose acetate, cellulose butyrate, ethyl cellulose, polyethyleneadipate, polyethylene azeleate, polydecamethylene succinate,polydecamethylene sebacate, etc. The telomerized polyester are alsocompatible with polyvinyl chloride, particularly upon the application ofmoderate heat.

The telomerized polyesters of this invention are particularly useful ascoating compositions on all types of substrates, including cellulose inits various forms, such as paper, wood, paper board, wood board, woodpulp, regenerated cellulose in film or fiber form, laminates of varioustypes including those prepared from fibrous fillers bonded with urea,melamine, epoxy and polyester resins, plaster board, concrete in itsvarious forms such as slabs, blocks and the like. They may also be usedas impregnants for porous bodies such as the compositions hereinabovenamed, as well as for synthetic and natural sponges, etc. Particularlydo they find use as bonding agents and adhesives for solid, porous andfoamed bodies. They can be used alone or admixed with each other or Withother copolymerizable monomers, unsaturated or saturated polymers, inthe absence or presence of dyes, pigments, plasticizers. For coating,impregnating or adhesive composi tions where the presence of smallamounts of solvent in the cured composition is not objectionable theycan be mixed with volatile or non-volatile solvents of a nonaromaticnature best suited to the particular application. The products resultingfrom the irradiation of the telomerized polyesters of this invention canvary from soft flexible bodies to hard rigid masses.

The telomerized radiation sensitive polyesters of this invention areparticularly useful in the preparation of the copolymers withunsaturated alkyd resins. In carrying this portion of the invention intoeffect, an esterification product of a polyhydric alcohol and an alpha,beta, unsaturated polycarboxylic acid is first prepared in accordancewith techniques now well known to those skilled in the alkyd resin art.

Any aliphatic polyhydric alcohol containing at least two esterifiablealiphatic hydroxy groups, or mixtures of such alcohols, can be used inpreparing the unsaturated alkyd resins. Examples of such polyhydricalcohols are ethylene glycol, di-, tri-, and tetra-ethylene glycols,thiodiglycol, glycerine, pentaerythritol, 1,4-dihydroxy-butene-2,dimethylol cyclohexane, dihydroxycyclohexane, etc. Any non-aromaticalpha-unsaturated, alpha betapolycarboxylic acid, or mixtures of suchacids, can be reacted with the polyhydric alcohol or alcohols to formthe unsaturated alkyd resin. Examples of such polycarboxylic acids aremaleic, fumaric, citraconic, mesaconic, acetylene dicarboxylic, aconiticcyclohexene dicarboxylic etc., itaconic and its homologues, as, forinstance, alpha methyl itaconic acid, alpha, alpha-dimethyl itaconicacid, etc. Anhydrides of these polycarboxylic acids can also beemployed.

In some cases, instead of using an unmodified, unsaturated alkyd resin,an unsaturated alkyd resin can be used which has been internallymodified by replacing a part, say up to about 75 mole percent, of theunsaturated polycarboxylic acid with saturated aliphatic polycarboxylicacids, such as succinic, adipic, glutaric, pimelic, sebacic, azelaic,suberic, tricarballylic, etc.

Anhydrides of these aids, if available, can also be used. The termpolycarboxylic acid as used generally herein is intended to include theanhydrides of the acids.

The esterification products of polyhydric alcohols with ethylenicpolycarboxylic acids, or with aliphatic polycarboxylic acids, can befurther modified by introducing as a reactant in the preparation of thealkyd resin, a monoesterifiable compound or compounds, more particularlya saturated or unsaturated normal or isomeric monohydric alcohol, ormixture thereof, a saturated or unsaturated monocarboxylic acid, ormixture thereof, or both such esterifiable monohydroxy organic compoundsas well as by the use of hydroacids.

Examples of non-aromatic monohydric alcohols which can be used asmodifiers of the alkyd resin are propyl, isopropyl, butyl, isobutyl,amyl, isoamyl, hexyl, octyl, decyl, dodecyl, tetradecyl, cetyl octadecylcyclohexyl, cyclopentyl, etc. The use of methyl and ethyl alcohol is notprecluded, but in general these alcohols are less satisfactory becauseof their lower boiling points. As monobasic acids there can be used, forexample, the unsubstituted saturated and unsaturated normal or isomericmonocarboxylic acids containing only one esterifiable group, such asacetic, propionic, butyric to stearic, inclusive, hexahydrobenzoic,hexahydrotoluic, furoic acids, etc.

The monoesterifiable compounds can be introduced into the esterificationbefore, during or after the esterification of the polyhydric alcoholwith the polycarboxylic acid under conditions that promoteinteresterification of the monesterifiable compound with theincompletely esterified polyhydric alcohol-polycarboxylic acid product.That is, the monoesterifiable compound is introduced into the reactionmass before all of the acid groups of the polyhydric acid, or all of thealcohol groups of the polyhydric alcohol have been esterified.

The term unsaturated non-aromatic alkyd resins, as used generally hereinand in the appended claims, is intended to include within its meaningboth unmodified esterification products of a non-aromatic polyhydricalcohol with a non-aromatic alpha-unsaturated, alpha, betapolycarboxylicacid and esterification products of these components which have beenmodified, for example, as briefly described hereinabove. An alternateterm is unsaturated aliphatic alkyd resins (including cycloaliphatictypes).

To achieve copolymerization of the unsaturated alkyd resin with thetelomerized polyesters of this invention, a solution or mixture of theunsaturated alkyd resin in the telomerized polyesters is first effected.Copolymerization of the components of the mixture is achieved rapidlyand advantageously by ionizing radiation, such as by atomic radiationfrom a reactor, or from cobalt 60, or by means of high energy electronsgenerated by an electron linear accelerator.

Typical examples of unsaturated alkyd resins are:

Alkyd Resin A-ethylene glycol itaconate Parts by weight Ethylene glycol23 Itaconic acid 52 11 The components are mixed and slowly heated in thecourse of one hour from room temperature to 190 C., in an inert nitrogenatmosphere, and held at this temperature for three to five hours.

Alkyd Resin Bethylene glycol maleate Parts by weight Ethylene glycol 31Maleic anhydride 32 The compounds are mixed and heated as in thepreparation of alkyd resin A to 180 C., and held at that temperature forfour to six hours.

Alkyd Resin Cacetic acid-modified diethylene glycol maleate Parts byweight Diethylene glycol 106 Maleic anhydride 88 Acetic anhydride Theingredients are mixed together and refluxed for one hour in an inertnitrogen atmosphere after which the reaction mixture is brought to 190C., which temperature is maintained for four to six hours.

It will be understood, of course, that this invention is not limited tothe use of the specific unsaturated alkyd resins mentioned above andthat a broad modification of the nature of the copolymer is possible byusing other unsaturated aliphatic alkyd resins or mixtures of suchresins. As illustrative examples of other unsaturated alkyd resins, thefollowing esterification products can be used, as illustrated in alkydresins D to I. Aromatic alkyd resin J is included for comparison.

ALKYD RESIN Components: Parts Diethylene glycol 160 Maleic anhydride 147E:

Diethylene glycol 106 Itaconic acid 130 F:

Glycerine 18.4 Itaconic acid 39.0

lithylene glycol 6.0 Maleic anhydride 19.6 'Hydroxypropyl acrylate 26.0

Ethylene glycol Maleic anhydride 29.4 Succinic acid 3.3 I:

Diethylene glycol 30.6 Maleic anhydride 17.6 Itaconic acid 15.6 I:

Diethylene glycol 30.3 Maleic anhydride 13.2 Phthalic anhydride 21.7

In many cases, instead of polymerizing a single telomerized polyesterwith a single unsaturated alkyd resin, mixtures can be used of two ormore telomerized polyesters with a single unsaturated aliphatic alkydresin, or a single telomerized polyester with two or more unsaturatedaliphatic alkd resins, or a mixture of two or more telomerizedpolyesters with two or more unsaturated aliphatic alkyd resins. Inconjunction With the alkyd resins, comonomers can be used which arecopolymerizable with the telomerized polyester or with the unsaturatedalkyd resins, or with both, for example, one or more telomerizedpolyesters can be used with one or more unsaturated aliphatic alkydresins together with methyl methacrylate.

In addition to, or in lieu of the methyl methacrylate. other comonomersor mixture of comonomers can be used, for example, the vinyl esters,that is, vinylacetate. and the vinyl esters of saturated andunsaturated, and aliphatic, monobasic and polybasic acids, and morespecifically the vinyl esters of the following acids: propionic.isobutyric, valeric, caprylic, capric, oleic, stearic, acrylic.methacrylic, crotonic, oxalic, malonic, succinic, glutaric. adipic,suberic, azelaic, maleic, fumaric, itaconic, mesaconic,hexahydrobenzoic, citric, trimestic, etc., as well as the correspondingallyl, methallyl, etc. esters of the aforementioned acids.

Other suitable comonomers are the acrylic and alkacrylic acids and theirderivatives, such as their esters. amides and corresponding nitriles,for example, acrylic acid, methyl acrylate, butyl acrylate, allylacrylate, ethylene glycol diacrylate, acrylonitrile, methacrylonitrile.methacrylic acid, methyl .methacrylate, etc.; the itaconie acidmonoesters and diesters, such as the methyl ethyl. allyl, dimethallyl,the maleic and fumaric acid monoesters, diesters and their amide andnitrile compounds, such as, ethyl allyl maleate, fumaryl diuitrile,dimethallyl fumarate, etc.; the ethers, such as methallyl allyl ether,vinyl allyl ether, vinyl methallyl ether, allyl crotyl ether. vinylcrotyl ether; cyanuric acid derivatives such as diallyl cyanurate,triallyl cyanurate, trivinyl cyanurate, or in general, triazinecompounds having at least one polymerizable or copolymerizableunsaturated group attached directly or indirectly to the triazine ring,as well as the partial, soluble or fusible polymers of the hereinabovelisted monomers, etc.

The modified unsaturated aliphatic alkyd resins of this invention can beused alone or with fillers, dyes, pigments, opacifiers, lubricants,plasticizers, natural and synthetic resins or other modifying bodies in,for example, casting, molding, laminating, coating applications, and asadhesives, impregnants, and protective coatings.

In coating, impregnating and similar applications, the mixed monomericor partially copolymerized materials. without added solvent can beapplied to the object to be treated and polymerized, with or without theapplication of heat and pressure, to form the final insoluble polymericcomposition in situ. These new synthetic materials can be used asimpregnants for many porous bodies, such as cork, pottery, felts, orfabricated bodies with interstices, such as the windings of electricalcoils, netted tibers, interwoven fibrous cotton or glass materials, etc.They can also be used for the production of wire coatings and windingtapes, and for protectively coating impervious articles, such as metals,or for coating and impregnating articles such as paper, wood, cloth,glass fibers in felted woven or other form, concrete, linoleum,synthetic boards, etc. These new synthetic materials can also beemployed in .making laminated fibrous sheet materials whereinsuperimposed layers of cloth, paper, glass fabrics or mats, etc., arefirmly bonded together with these new compositions. Also, these newmixtures comprising at least one telomerized polyester of this inventionand at least one unsaturated aliphatic alkyd resin, with or withoutmodifying agents, can be cast under pressure while being irradiated.

In preparing the interpolymerization products of the unsaturatedaliphatic alkyd resin and the telomerized polyester, the unsaturatedalkyd resin can constitute as much as 98 or 99 percent by weight of thewhole. In other cases the telomerized polyester alone, or admixed withaliphatic comonomers or modifiers, can constitute as much as 98 to 99percent by weight of the whole.

In general, the proportions of the components used in a particularformulation will depend upon the particular properties desired in theinterpolymer. For most applications, it is preferred to use 30 topercent of the unsaturated aliphatic alkyd resin and from 10 to 70percent of the telomerized polyester, since within these ranges in- 13terpolymers best adapted for most commercial applications can beproduced.

Within these ranges the new interpolymers have a Wide range ofproperties. For example, depending upon the particular telomerizedpolyester or mixture of telomerized polyesters used With the particularunsaturated aliphatic alkyd resin the particular proportions thereof,the conditions of polymerization, such as the temperature, pressure,presence or absence of additives, etc., the irradiation dose, and theextent of polymerization, they can vary from soft flexible bodies tohard rigid masses of varying resistance to solvents.

In the intermediate stages of copolymerization, some form fluidcompositions of varying viscosities and may be so used. For coating orimpregnating applications where the presence of a small amount ofsolvent in the cured composition is not objectionable, the mixedstarting component can be diluted with volatile or non-volatile solventsor diluents best suited for the particular service application, and thencan be polymerized after the application of the solution to theparticular article to be coated or impregnated, or impregnated andcoated. By suitable selection of the starting material and theconditions of the interpolymerization, interpolymers can be obtained inan insoluble, infusible state practically resistant to the destructiveetfect of other chemical bodies, such as acids, bases, salts, solvents,swelling agents, and the like.

When it is desired to modify the properties of the polymers of thetelomerized polyesters of this invention, this can be accomplished bycopolymerizing a mixture comprising at least one telomerized polyesterwith at least one copolymerizable unsaturated ethylenic, or acetylenichydrocarbon radical, more particularly, a CH =C di-amides, and thecorresponding imides, etc.; the vinyl ethers, for example, vinyl butylether, vinyl isobutyl ether, vinyl cyclohexyl ether, the dienes, etc.,for example, butadiene, isoprene, dimethyl butadiene, etc.

In preparing copolymers of the telomerized polyesters with otherpolymerizable comonomers such as methyl methacrylate, acrylonitrile, andthe like, the telomerized polyesters can constitute as little as 0.1percent by Weight of the Whole, whereas in other cases, the telomerizedpolyesters alone can constitute as much as 98 to 99 percent of thewhole. As in the case of the copolymers with unsaturated aliphatic alkydresins, the proportion of the components in a particular formulationwill depend upon the particular comonomers used and the particularproperties desired in the copolymer. The polymers and copolymers can beprepared most readily by ionizing radiation.

Various methods of practicing the invention are illustrated by thefollowing examples. These examples are intended merely to illustrate theinvention and not in any sense to limit the manner in which theinvention can be practiced. The parts and percentages recited thereinand all through this specification, unless specifically providedotherwise, refer to parts by weight and percentages by Weight.

Example I In a suitable reaction apparatus equipped with a stirrer,reflux condenser, inert gas inlet, heating mantle and thermostaticcontrol for the reactor, are placed 284 parts of glycidyl methacrylate,146 parts of adipic acid, 2 parts of hydroquinone. The mixture isheated, with stirring in a nitrogen atmosphere, at 130 C. for eighteenminutes, and there is obtained the product radical, such as vinyl,allyl, methallyl, vinlidene, etc., or with a copolymerizable compoundcontaining a OH OH Example II When 256 parts of glycidyl acrylate areused in the reor a -CH==C or a CH=CH grouping, for examaction of ExampleI with adipic acid instead of the 284 ple, as in vinylidene fluoride,vinylidene cyanide, vinyl propionate, maleic anhydride, or its estersand amides, methyl maleic anhydride, tetrafluoroethylene, etc.

Additional examples of copolymerizable comonomers are monomeric orpartially polymerized vinyl esters, such as the acetate, propionate,etc.; vinyl ketones, methvinyl ketones, olefinic nitriles, such asacrylonitrile, methacrylonitrile, fumaryl nitrile,beta-cyano-ethylacrylate, acrylic and methacrylic esters, for example,methyl acrylate, ethyl acrylate, propyl parts of glycidyl methacrylate,there is obtained the product OH OH Example III A mixture of 415 partsof the product of Example I, 204 parts of acetic anhydride and 1 part oftributyl amine are refluxed in a nitrogen atmosphere for one hour. Thenthe acetic acid by-product is removed by distillation under a reducedpressure of 5 mm. and there remains in acrylate, butyl acrylate, ethylmeththe reaction flask 497 parts of the product Example IV The procedureof Example III is repeated except that instead of acetic anhydride thereis used 252 parts of acrylic anhydride containing 1% of tertiary butylalcohol, and there is obtained CH3 CH3 OOCOH=CHg OOCCH=CH2 1 5 Example VBy repeating the procedure of Example III a number of times using molarequivalents respectively of the appropriate anhydrides, namely,methacrylic, stearic, methoxy acetic, acetic, acrylic and butyricanhydrides, the

1 6 Example VII The procedure of Example VI is repeated a number oftimes using molar equivalents of glycidyl acrylate Instead of glycidylmethacrylate, and there are Obtained 5 seven products of the generalformula product of Example I is readily converted to the followingderivatives:

I (a) CHZ C C O O CHzCIICHzO O C(CH:) C O O CHgCHCHzO O C C=OH3 I O O CC=CH O O C G18H37 O O CisHst O O C CHzO CH3 CH3 I I CH2=C CO 0 CHzCHCHzOO C(CHzhCO O CHzCHCHzO O C C=CHg I I CHFC C O O CHzCHCHzO O C (0112040 0O CHzCHCHzO O C C=CH2 O O C CHzO CH3 Example VI To the reactor ofExample I there is added, in a number of respective experiments,appropriate proportions of ethylene glycol and succinic anhydride andreacted at 180 C. for six hours to give a series of products having thegeneral formula HOOC(CH C0 OCH CH OOCCH CH COJ OH wherein n equals 1, 3,5, 10, 12, 14 and 15. These are in turn each reacted with two molarproportions of glycidyl methacrylate to give seven products respectivelyof the general formula where n=1 for sample a 12:3 for sample b' n=5 forsample c 12:10 for sample d n=l2 for sample e 12:14 for sample f n=l5for sample g where n=1 for sample a 11:3 for sample b n=5 for sample 0'n: 10 for sample 11' n=12 for sample :2 11:14 for sample 7" n: 15 forsample g.

Example VIII The seven products of Example VI, a to g inclusive, aretreated with acetic anhydride by the procedure of Example III and thereare obtained the acetyl derivatives of the general formula I I cm=cc 0 0cmoncmo 0 (3 0119 0 oto CHgCHgO 0 0 011920 operator-tome 0 oc=cm OOCCHaand when acrylic anhydride is used as the acylating agent according toExample 1V, there are obtained the respective products I O O C CH=CH2with the values of 21 corresponding in each case to those of Example VI,where 21 has the original numerical value of 1 to 15.

Example 1X When in Examples I, II and VI, other saturated aliphaticdicarboxylic acids, such as glutaric, dodecanedicarboxylic acid,hexahydrophthalic, etc., are used instead of adipic and succinic acid,the corresponding hydroxy substituted diacrylyl terminated polyestersare obtained. Similarly, when other aliphatic diols such ashexamethylene glycol, diethylene glycol, dihydroxycyclohexane,hexahydroxylylidene glycol etc., are used instead of ethylene glycol,the corresponding hydroxy substituted diacrylyl terminated polyestersare obtained. These hydroxy substituted polyesters are readily acylatedby the procedures given in Examples III, IV, VII and VIII.

Example X The procedure of Example VI is repeated a number of timesusing equivalent quantities of an aromatic dicarboxylic acid, phthalicanhydride, instead of the aliphatic dicarboxylic succinic anhydride, andthere is obtained a series of products of the general formula o o oCH=CH2 Example XIV The seven telomerized polyesters of Example VIa' toVIg inclusive are subjected to irradiation and those having values of nfrom 1 to 14 crosslink under dosages increasing from 2 megarad for n:1to 4.6 megarads for 21:14. For n=15 crosslinking occurs at 6.7 megarads,indicating an economical upper limit for values of n being less than 15.When, however, an average value of less than 15 can be obtained bymixtures of polyesters of 11 being smaller than 15, for example n:1 to12 admiX d With a polyester of n:15, for example equal mixtures f esterof 21:15 with esters of 21:1 and 5 respectively, crosslinking occurs at3.1 and 4.2 megarads respectively.

Irradiation of the seven telomerized samples VIIa' to VIIg and W111:inclusive shows similar results, indicating that 21:14 is an economicalupper limit.

Example XV The seven tetraacrylyl polyesters of Example VIIIb aresubmitted to irradiation of the linear accelerator and all of themcrosslink in the range of 1 to 3.2 megarads indicating the marked effectof the additional acrylyl group which not only lowers the dosagerequirements but I Cllz f l C O O CHz(|JIICIIgO[O C C ILC O OCHzCIIgO],,O C CaHrC O O CHZCHCHZO O C C=CH2 21: 10 in sample 0' 21:12in sample 11.

Example XI also raises the upper limit of the value of n. The productsvary from hard, tough, insoluble, infusible solids at 11:1 to tough,infusible, insoluble, progressively more elastic polymers at 21:15.

Example XVI A cellulose sponge is impregnated with the telomerized Theprocedure of Example V1 is repeated using equivpolyester of Example VIa'dissolved in an equal weight alent quantities of an aromatic dialcoholp-xylylidene glycol, HOCH C H CH OH instead of ethylene glycol, andthere is obtained a series of products of the general formula CH CH2 inwhich 11:1 in sample a 21:5 in sample I) 21:10 in sample 0' 11:15 insample d.

Example XII Example XIII The tetraacrylyl substituted polyesters ofExamples IV, Va and Ve are irradiated in an open container. Thesecrosslink at irradiation dosages within the range of 0.90

Example XVII A printed face sheet whose design corresponds to that of awood grain is impregnated with a mixture of the telomerized polyester,(1) Wu, 50 parts; (2) VIc, 20 parts; (3) VId, 10 parts; and (4) VIIIbwhere 11:2, 5 parts, and alkyd resin G, 15 parts; so that the sheetconsists of 60 parts of polyester mixture and 40 parts of sheet byweight. This impregnated sheet is laid over a woodchip board and thewhole irradiated to 4 megarads. There is obtained a finished boardhaving the appearance of a fine grain, high gloss, varnished wood whichis resistant to water, alcohol, acetone and most of the common organicsolvents.

Example XVIII Parts Alkyd resin A Telomerized polyester Example III 20The alkyd resin A and the telomerized polyester are thoroughly anduniformly mixed and subjected to ioniZ- ing radiation and converted toan insoluble, infusible hard product at a dose of 3.6 megarads.

Fillers such as wood fiour, alpha cellulose, shredded cellulosederivatives, asbestos, paper, cloth, sand, silica, calcium sulfate, etc.can be coated or impregnated with the mixture and the mass hardened byirradiation to produce formed articles of good appearance and excellentphysical properties and improved heat-resistance.

To improve the heat-resistance further the foregoing procedure ismodified using a higher ratio of telomerized polyester to theunsaturated alkyd as follows:

Parts Alkyd Resin A 50 Telomerized polyester III 50 and Alkyd Resin A 75Telomerized polyester III 25 Compositions of the kind illustrated inthis example have the advantage that they do not contain radicalinitiators and can be stored for long periods of time, and still arereadily cured without the addition of catalyst by the simple expedientof subjecting them to irradiation.

Example XIX The procedure of Example XVIII is repeated except thatinstead of Alkyd Resin A, there is used Alkyd Resin B and infusibilityand insolubility is obtained at 3-4 megarads of irradiation.

The composition of Examples XVIII and XIX can be used as roomtemperature, low pressure laminating resins for the preparation ofreinforced laminates from glass mats or fabrics.

It will be understood of course that this invention is not limited tothe interpolymerization of Alkyd Resins A and B with the telomerizedpolyester of Example III, and that another acrylyl telomerized polyesteralone or in combination can be used, for example, the telomerizedpolyesters of Examples I, II, and IV-IX inclusive, can also be used.

In contrast, when the aromatic containing telomerized polyesters ofExamples X and XI are used, irradiation doses in excess of 18 megaradsare required to produce hard, infusible polymers.

Similarly, high irradiation doses in excess of 16 megarads are requiredwhen the aromatic containing alkyd resin J is used with the acrylyltelomerized polyesters in contrast to the use of alkyd resins C, D, E,F, H and I which become infusible and insoluble in the range of 3.8 to4.0 megarads.

The use of unsaturated alkyl resin G, which is an acrylyl terminatedunsaturated alkyd in admixtures with the acrylyl telomerized aliphatictype polyesters, for example, the polyesters of Examples I, II and HI isparticularly beneficial since in all cases crosslinking occurs withinthe range of 1.8 to 2.1 megarads.

or concrete block, a porcelainized finish is obtained when the coatingis irradiated.

Example XXI Fifty parts of the telomerized polyester of Example VIIIa isdiluted with 10 parts of glycol dimethacrylate and a concrete panelAs-inch thick is impregnated with this solution and the panel irradiatedto a dosage of 3.5 megarads; a water-impervious panel is obtained.

Example XXII A mixture of 80 parts of exploded wood fibers of the typeused to prepare fiber board, 12 parts of the telomerized polyester ofExample Xb' 1 part of zinc stearate and seven parts of linseed oil aremulled to uniformity, pressed into a board and given 4.8 megarads ofirradiation. There is obtained a well knit, hard board which is readilypaintable with either solvent-type paints, or aqueous emulsion paints.

Example XXIII Four parts of the polymer of Example VIe' are added to 10parts of water containing 0.5% of sodium dioctyl sulfosuccinate as anemulsifying agent and the mixture emulsified in a colloidal mill. Theemulsion of the telomerized polyester is added to 50 parts of prepuifedpolystyrene beads mixed and the mixture tumbled until all the beads areuniformly coated. The water is then allowed to evaporate from the coatedfoamed beads which adhere slightly to each other. The coated foamedbeads are then placed in a container such as a cardboard box andirradiated to a dose of about 4 megarads. By this process there isobtained a foamed structure in which the beads are all bonded withinfusible bonds to each other, the shape of which conforms to the formof the container.

Example XXIV A uniform mixture of 40 parts of the diacrylyl polyester ofExample VIa and parts of a plastisol grade of polyvinylchloride having amolecular weight of about 25,000 is prepared. This is melt-extruded intopipe and given an irradiation dose of 3 megarads. The polyvinylchlorideis not degraded by this small dosage and the treatment makes the pipeinsoluble and infusible so that it withstands hot water 210 F. and hotsaturated brine at 215 F. without softening. It also withstands hotsolutions of acetic acid, toluene, carbon tetrachloride, etc.

While certain features of this invention have been described in detailwith respect to various embodiments thereof, it will, of course, beapparent that other modifications can be made within the spirit andscope of this invention and it is not intended to limit the invention tothe exact details shown above except as they are defined in thefollowing claims.

The invention claimed is:

1. The highly radiation-sensitive telomerized diacrylyl polyester havingthe formula CH2=O C 0 O CH2(IJHCH O O GRGOIORO O CRCOLO CHzC'JHCHQO O CC=CH2 Example XX A smoothly sanded pineboard 12 inches by 36 inches and/S-iIICh. thick is coated on one surface with a mixture of equal partsof the polyesters of Example VIII to produce a layer of polyester0.005-inch in thickness, and the board is progressed under the sweepingbeam of the linear accelerator to be given a uniform dose of 3 megarads.The finished board has the appearance of a high gloss varnished lumber.

When the above polyester mixture is blended and milled with 60 parts oftitanium dioxide pigment (paint grade) and the pigmented polyesterapplied to wood, fiber board OX 0X R wherein n has a value of 0-14;

R represents a connecting linkage between two adjacent car boxylicradicals selected from the class consisting of a single valence bond anda divalent saturated aliphatic hydrocarbon radical having 1-10 carbonatoms;

R is a divalent saturated aliphatic hydrocarbon radical having 2-10carbon atoms;

R" is a radical selected from the class consisting of hydrogen andmethyl;

R" is a radical selected from the class consisting of hydrogen and analiphatic hydrocarbon radical having 1-18 carbon atoms; and

21 22 X is a radical selected from the class consisting of 7. Theprocess of claim 6 in which said diacrylyl polyhydrogen and an acylradical of the formula RCO. ester is intimately admixed with acopolymerizable mono- 2. The telomerized diacrylyl polyester of claim 1,mer, said diacrylyl polyester comprising 1-99 percent by which has theformula weight of said copolymerizable mass and said copolymer- CHFC]? CO O CHzCHCI-IrO O C CHzCHgC O O CHzCHCHzO O CC=CH2 CH3 OH OH CH3 3. Thetelomerized diacrylyl polyester of claim 1 which has the formula izablemonomer comprising 99-1 percent by weight of said copolymerizable mass.

[CH3 (3H CHE CCOOCHECHCHQOOCCHZCHBCOOCHzCHCHgOOCC CH'J OOCCH CHZOOOCH=CH2 4. The telomerized diacrylyl polyester of claim 1, 8. Theprocess of claim 6 in which said diacrylyl polywhich has the formulaester is in intimate admixture with an unsaturated ali- 5. Thetelomerized diacrylyl polyester of claim 1, phatic alkyd resin, saiddiacrylyl polyester comprising which has the formula 10-70 percent byweight of said copolymerizable mass CHg=CHCH COO CHZCHCHQOO C CHQCHQCO[OCH CHQOOCCH CH COlnCHgCHCI'IgOOCH=CH1 OCHgCH=CHg OCHQCH=CHQ 6.Aprocess for producing an improved polyester resin and said unsaturatedaliphatic alkyd resin comprising composition comprising the treatment ofa highly about -90 percent by weight of said copolymerizableradiation-sensitive telomerized diacrylyl polyester having mass. theformula 30 wherein n has a value of 0-14; 9. The process of claim 6 inwhich said diacrylyl poly- R represents a connecting linkage between twoadjacent ester has the formula CH2=(|3 C O O CHQCHCHZO O C CHgCH C O OCHgCHCH O O C C=CH CH3 OH OH CH3 carboxylic radicals selected from theclass consisting 10. The process of claim 6 in which said diacrylyl of asingle valence bond and a divalent saturated polyester has the formula(3H3 (EH3 CHFC o o o CHJffHCIIQO o C CHQCIIZC o o CIIQOHOHQO o o o=oHgOOCCH:CH2 OOCCH=CII2 aliphatic hydrocarbon radical having 1-10 carbon11. The process of claim 6 in which said diacrylyl atoms; polyester hasthe formula CIT-5:0 C O O CHgCHCHaO O C CHsCHzC O[O CHaCHzO O C CHzCHeC0],.0 CHaClHCHzO O C C|=CH OH; OH OH CH;

R is a divalent aliphatic hydrocarbon radical having 12. The process ofclaim 6 in which said diacrylyl 21O carbon atoms; polyester has theformula CHr-CHOHgC O O CH2CHCH2O O C CHzCHzC O[O CHzCHzO O C CHECHQCOIHCHQCHCHZO O CH=CH2 OCHzCH=CHz OOHQCH=CH2 R is a radical selected fromthe class consisting of 13. A radiated polymeric product producedaccording hydrogen and methyl; to the process of claim 6. R is a radicalselected from the class consisting of 14. A radiated polymeric productproduced according hydrogen and an aliphatic hydrocarbon radical havtothe process of claim 7. ing 1-l8 carbon atoms; and 15. A radiatedpolymeric product produced according X is a radical selected from theclass consisting of to the process of claim 8.

hydrogen and an acyl radical of the formula R"CO; 16. A radiatedpolymeric product produced according with at least about 0.5 megarad andno more than about to the process of claim 9.

8 megarads of high energy, ionizing radiation equiv- 17. A radiatedpolymeric product produced according alent to at least 100,000-electronvolts. to the process of claim 10.

18. A radiated polymeric product produced according to the process ofclaim 11.

19. A radiated polymeric product produced according to the process ofclaim 12.

20. A process for producing an improved polyester resin compositioncomprising the treatment of a highly radiation-sensitive telomerizeddiacrylyl polyester having the formula:

CHr-C C O 0 CH2CHCHzO 0 CRC 0 [OB/O O CRCOLO CHgGHCHzO O C C=CH whereinn has a value of 0-14;

R represents a connecting linkage between two adjacent carboxylicradicals selected from the class consisting of a single valence bond anda divalent saturated aliphatic hydrocarbon radical having 1-10 carbonatoms;

R is a divalent aliphatic hydrocarbon radical having 2-10 carbon atoms;

R" is a radical selected from the class consisting of hydrogen andmethyl;

R is a radical selected from the class consisting of volts.

References Cited UNITED STATES PATENTS 2,379,251 6/1945 Muskat et al260485 2,973,331 2/1961 Kraft 26076 3,336,418 8/1967 Dill 260884 OTHERREFERENCES Burlant and Hinsch: tat-Initiated Crosslinking of UnsaturatedPolyesters, Journal of Polymer Science, vol. 61, pp. 303-309 (1962).

Chemical Abstracts, v01. 54, p. 624f.

20 MURRAY TILLMAN, Primary Examiner RICHARD B. TURER, Assistant ExaminerUS. Cl. X.R.

22 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 41; 71 Dated December 23, 1969 Inventor(s) Gaetaho F; D'Alelio It isvertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Column 2, line 29 (Eg.la) should be --(Eq.la)

Column 2 line 49 (Eg.lb) should be --(Eq.lb)

Column 5, line 69 7OR'OOCRCOA should be OR'OOCRCQ7 Column 9, line 32polyester should be --polyesters--;

Column ll, line 67 alkd should be -alkyd--;

Column 13, line 35 vinlidene should be --vinylidene-- Column 17, line 73te raacrylyl should be --tetraacrylyl--.

SIGNED AND QFALED SEP 29 1970 Attest:

Edward M. Fletcher, 11-. mm m. .m.

Gomissioner at Patents Attcsting Officer

